Well fishing tool



Sept. 6, 1955 c. J. BOYD 2,717,172

WELL FISHING TOOL Filed July 17, 1953 INVENTOR 23 CHARLES J. BOYD www ATTORNEY ,www

United States Patent WELL FISHIYG TOOL Charles I. Boyd, Santa Fe, N. Mex.

Application July 17, 1953, Serial No. V368,749

Z Claims. (Cl. 294-86) This invention relates to tools for extracting bodies which have become broken or detached in wells, and more particularly to a tubular tool having one or more gripping elements for automatically engaging such detached objects to enable the removal of the same from the well.

Water wells of the deep variety utilize a piston and cylinder at the bottom of the bore. The bore is lined with a pipe casing. The piston is reciprocated in a vertical direction by a piston rod extending from the piston to a point above ground where it -is mechanically connec'ted to a pump handle or self-powered reciprocating means. The piston rod is generally made up of Wood sections or rods each about sixteen feet in length, and a sufficient number of these sections or rods are coupled together to `extend the length of the bore. -It is not infrequent in certain parts of the country such-as the ISouthwest for such wells to extend to a depth of three hundred feet.

It sometimes happensv that a piston rod breaks or the sections become detached. Insuch a caseit is imperative that the lower detached portion be retrieved from the well as quickly as possible for the reason that 'the absence of a water supply in isolated areas Vmay result in serious consequences. Although devices such -as shown in .patents, French 743,854, Jones 1,734,468, Larson 1,609,370

and Holland 2,614,881 for -retrieving such detached .parts :i:

are present in the art, they sometimes `encounter such unfavorable conditions in the well casing Vthat they are unable to work. In such cases the very expensive and time consuming chore of pulling the casing must be undertaken. 'Y

One of the reasons that prior art devices sometimes fail to operate is that the top end of the detached or broken rod section almost invariably leans against the .side of the well casing. Any protuberance onthe well fishing tool which prevents Vit from Vmoving in the casing adjacent the inner wall of the casing causes its lower end to simply jam against the top of the detached or broken rod section.

Another reason for the failure of prior art devices to operate in all cases resides in an undue thickness in the material of the fishing tool. If a rod section is detached and not broken, it has at its end an elongated metal attachment device having a flat surface in line with the axis of the rod section and several protruding rivets affixed to the attachment device normal to its fiat surface. Anything other than a sharp cylindrical end on the fishing tool is apt to catch on the rivets and so fail to slip down over the rod section.

Another cause of failure of prior art devices to operate under certain circumstances has been the provision of gripping elements or dogs which are hingedly affixed to the fishing tool barrel in such a way that the hinge portion presents either a protuberance on the outside of the barrel or an unsatisfactory obstruction on the inside of the barrel. If the protuberance is on the outside, the fishing tool must be smaller in cross section than the lCC inside of the well casing with the lresult that its lower edge strikes and jams against the end of the broken or detached section. If the obstruction is on the inside of the fishing to'ol, is it'frequently not usable because it is unable to p'ass and receive the vbroken or detached rod section.

Still another difficulty with prior art devices resides in the absence of means for positively limiting the downward arc of motion of the gripping device. 1f the gripping device is longer than the cross section -of the housing itis apt to cut in two the section of rod which it engages.

"If it is shorter Vthan the internal cross section of the housing and an aged rod is engaged, the gripping device simply sinks into the rod until it passes the horizontal position and allows the fishing tool to slide oil the rod. These results are apt to be serious if the lbroken rod section has been lifted a .considerable dista-nce before it becomes disengaged and dropped. It is likely that the well valve and lower casing members will be damaged to such an extent as to require the removal of the entire casing to enable repairs 'to be made.

It is accordingly a primary object of this invention to provide a well fishing tool or pump rod retriever of such improved character as to invariably operate to retrieve a detached rod section in a well casing.

Other objects and 'advantages will. become apparent ,from consideration of the Afollowing description and the 'accompanying drawing made a part of Ithis specification.

Figure 1 is a side elevation of a complete -well fishin-g tool constructed in accordance with this invention.

Figure `2 is an upper end fragment of the fishing tool of Figure 1 showing alternative attaching means.

Figure .3 is an enlarged fragment in perspective of the tool 'of Figure l'showing gripping device details.

Figure 4 is an enlarged perspective similar to Figure .3 showing the gripping device in a raised position.

Figure 5 is a cross section taken on the plane 5 5 of Figure l, but '-with dog I1 in an upward position, contactin'g Spring 19.

, `Referring to the drawing, Figure l, it is seen Vthat my novel pump rod retriever comprises an elongated .cylindrical barrel or housing 9 having'oue or more gripping devices or dogs 11 hingedly affixed to the barrel along its lengthfand an attachment member -13 fastened to the upper end .of the barrel.

Provision is made xin the barrel 9 for accommodating thefgripping device or dog by cutting out of the barrel a partial-elliptical .shaped portion. The partial-ellipse is Atoibtainedby slicing out a portion -of .the barrel by .an in- `wardly inclined cut terminating at the ends of a right cylindrical arc of approximately The `opening in the barrel 'therefore is 'bounded on the base by a right cyclindrical arc and on the sides by the partial-ellipse. A short axial distance below the circular surface which forms the base of each barrel opening, a narrow cylindrical slug of about 40 of arc of the barrel material is removed, with the long dimension centrally located and parallel to the said circular base of the opening to thereby provide integral with thebarrel an integral hinge pin 1S shown most clearly in Figures 3, 4 and 5. The material of the hinge pin between its ends is deformed inwardly sufficiently to provide a substantially straight hinge pin. Because the hinge pin extends through only between about 40 to 60 of arc it presents practically no internal obstruction to the barrel. This manner of providing the hinge pin is preferred but is not intended to be limiting, it being apparent that a pin axed in place across the top of the recess in any known manner is equivalent.

Each of the gripping devices or dogs 11 are roughly of elongated isosceles triangular shape with a shorter side or base 24 having a radius of curvature substantially equal to the radius of curvature of the outside surface of the housing. Themiddle portion of the base of the gripping dog is provided with an integral colinearly extending tongue which is looped down and around the hinge pin 1S to provide a hinge 17. The hinge is formed completely below the nether surface of the dog. This construction causes the arcuate portions of the dog adjacent the hinge to act as stops against the barrel opening base when the dog is in a position normal to the axis of the housing. Accordingly, a strong and absolutely limiting stop is provided to prevent the dog from rotating into a downward position so that even very soft pump rods are irmly held for removal from the well casing.

Both the barrel and gripping dogs are fabricated of thin material, preferably chrome molybdenum steel in order to provide the least possible obstruction to objects to be retrieved in a well casing.

Each gripping dog is of a length not over 80% of the internal diameter of the barrel and is provided at its end opposite the base with two tines formed by removing a V-shaped portion of the material symmetrically about the vertical median line of the dog. The ends of the tines are sharpened. The pocket so formed between the tines acts to compress the material of a pump rod and thereby provides superior gripping qualities especially when pulpy or rotted well rods are being retrieved.

In order that the gripping dogs will have an initial biting or gripping action, an inwardly coercing spring 19 is provided. This spring is a substantially rectangular tine of springy material welded or screwed to the material of the barrel just above the apex of the semi-elliptical surfaces of the window and being aligned and bearing against the outside surface of the gripping dog proximate the hinge portion. The spring 19 is of thin material so that even if a rod to be retrieved is of cross section nearly equal to the bore of barrel 9, there is negligible likelihood of binding in a well casing.

It follows from the foregoing description that a Well fishing tool of exceedingly simple, rugged and effective construction is effected, The tool is utilized simply by being suspended by a suitably strong rope or wire secured to the eye or bale 13. If desired, the rope or wire may be dispensed with and the sections of rod which were above the broken part can be secured to the ear bale 21 shown in Figure 2 and the tool lowered into engagement with the detached segment.

I claim:

1. A well rod extracting device comprising an elongated tubular housing having a top end and a bottom end, at least one opening in the side wall of the housing between the top and bottom ends, said opening being formed by lateral edges of the housing diverging from av point on the surface downwardly and inwardly of the housing to encompass at their lower ends an arc of approximately 120, said opening lower edge being formed by an upper edge portion of the housing lying in a radial plane and ending between the lower ends of the opening lateral edges, an elongated central portion of said upper edge portion of the housing being recessed and a hinge pin aixed to the upper edge portions of the sides of the recess and bridging said recess and having its upper surface on a plane substantially in the plane of said upper edge portion of the housing, an elongated gripping dog having a length slightly less than the diameter of the housing and having a base end and a gripping end, said base end having curved edges with the curvature being proximate the curvature of said opening lower edge, said curved edges terminating in a centrally located looped portion, said looped portion surrounding said hinge pin to thereby hinge said gripping dog; spring means affixed to the housing and coercing the gripping end of said gripping dog inwardly and downwardly, and means for attaching a tractor device to the upper end of said housing, and the interior of said bottom end being unobstructed.

2. A well rod extracting device comprising an elongated tubular housing having a top end and an open bottom end, said housing having an opening in its lateral wall between the top and bottom ends, said opening being bounded laterally by edges of the housing lying on a plane passing from a point on the housing surface, corresponding to the top of the opening, downwardly and inwardly to lower ends which intercept the ends of an arc of approximately 120, and said opening being bounded on the bottom by a circumferential upper edge of the housing which lies in the plane of and terminates at the lower ends of the said lateral edges of the housing; an elongated central circumferential portion of the said upper edge of the housing being relieved and a hinge pin ailixed at its ends to the housing and bridging the edge relief and having its upper surface lying substantially in the plane of the said upper edge; an elongated gripping vdog having a length not exceeding the diameter of the housing, having lateral edges and having a gripping end and a baseend, the base end having a tongue portion of Width slightly less than the length of the housing upper edge relief, said tongue portion being looped downwardly around said hinge pin, said gripping dog base portion having a width substantially equal to a chordy of the housing exterior surface extending across the greater part of the said housing circumferential upper edge, spring means supported on the housing and bearing against the gripping dog near thekhinged portion thereof to urge the same inward and downward, means for attaching a lifting device to the upper end of the housing.

References Cited in the le of this patent UNITED STATES PATENTS '1,780,699 Brown Nov. 4, 1930 2,542,445 Young Feb. 20, 1951 2,614,881 Holland Oct. 21, 1952 

